1. Department of Mechanical and Aerospace Engineering, The George Washington University, Washington, DC, USA;
2. The University of Akron, Akron, OH, USA;
3. Translational Research Centre of Regenerative Medicine and 3D Printing Technologies of Guangzhou Medical University, The Third Affiliated Hospital of Guangzhou Medical University, Guangzhou City, Guangdong Province, People’s Republic of China;
4. School of Biological Sciences and the Center for Biomedical Engineering & Rehabilitation Science, Louisiana Tech University, Ruston, LA, USA;
5. Department of Biomedical Engineering, The George Washington University, Washington, DC, USA;
6. Department of Medicine, The George Washington University, Washington, DC, USA